Optical fiber cable connection structure and method for manufacturing optical fiber cable

Abstract

An optical fiber cable connection structure includes: optical fibers divided into a first bundle and a second bundle in a middle portion of an optical fiber cable in a longitudinal direction of the optical fiber cable; a first fixing portion that integrally fixes the optical fibers of the first bundle in the middle portion; a second fixing portion that integrally fixes the optical fibers of the second bundle in the middle portion; and an optical path that is disposed between the first bundle and the second bundle, holds a space between the first bundle and the second bundle in the longitudinal direction, and optically connects the divided optical fibers to each other.

The invention claimed is: 
     
       1. An optical fiber cable connection structure comprising:
 optical fibers divided into a first bundle and a second bundle in a middle portion of an optical fiber cable in a longitudinal direction of the optical fiber cable; 
 a first fixing portion that integrally fixes the optical fibers of the first bundle in the middle portion; 
 a second fixing portion that integrally fixes the optical fibers of the second bundle in the middle portion; and 
 an optical path that is disposed between the first bundle and the second bundle, holds a space between the first bundle and the second bundle in the longitudinal direction, and optically connects the divided optical fibers to each other, wherein 
 at least one of the optical fibers of one or both of the first bundle and the second bundle extends in an oblique direction with respect to the longitudinal direction, 
 the optical fibers of the first bundle are embedded in a resin included in the first fixing portion, and 
 the optical fibers of the second bundle are embedded in a resin included in the second fixing portion. 
 
     
     
       2. The optical fiber cable connection structure according to  claim 1 , wherein the optical path includes an optical resin having light transmissive properties and disposed on at least one of cut surfaces of the first bundle and cut surfaces of the second bundle. 
     
     
       3. The optical fiber cable connection structure according to  claim 1 , wherein
 the optical path includes self-assembled optical waveguides including a photocurable resin that individually connects the divided optical fibers, and 
 the divided optical fibers extend from cut surfaces of the first bundle and the second bundle. 
 
     
     
       4. A manufacturing method of an optical fiber cable, comprising:
 fixing optical fibers with a resin to form a fixing portion in a middle portion of an optical fiber cable in a longitudinal direction of the optical fiber cable, wherein at least one of the fixed optical fibers extends in an oblique direction with respect to the longitudinal direction; 
 cutting the optical fibers in the fixing portion to divide the optical fibers into a first bundle and a second bundle; 
 optically connecting the divided optical fibers to each other in a state where a space between the first bundle and the second bundle corresponds to a length of a shaving margin in cutting the optical fibers; and 
 in fixing the optical fibers, forming the fixing portion by accommodating the middle portion in a case and injecting the resin into the case. 
 
     
     
       5. The manufacturing method according to  claim 4 , further comprising:
 in optically connecting the divided optical fibers, disposing an optical resin having light transmissive properties on at least one of cut surfaces of the first bundle and cut surfaces of the second bundle, wherein 
 a thickness of the optical resin interposed between the cut surfaces of the first bundle and the cut surfaces of the second bundle corresponds to the length of the shaving margin. 
 
     
     
       6. The manufacturing method according to  claim 5 , further comprising:
 in fixing the optical fibers, forming the fixing portion by accommodating the middle portion in a case and injecting the resin into the case; 
 in cutting the optical fibers, dividing the case into a first case divided body integrally fixed to the first bundle and a second case divided body integrally fixed to the second bundle by cutting the case together with the optical fibers; and 
 in optically connecting the divided optical fibers, positioning the divided optical fibers by positioning the first case divided body and the second case divided body. 
 
     
     
       7. The manufacturing method according to  claim 4 , further comprising in optically connecting the divided optical fibers:
 filling a portion between the first bundle and the second bundle with a photocurable resin in a state where the space corresponds to the length of the shaving margin; and 
 forming a self-assembled optical waveguide that connects together the optical fibers of the first bundle and the optical fibers of the second bundle by allowing light to pass through at least one of the optical fibers of the first bundle and the optical fibers of the second bundle and launching the light toward the photocurable resin to cure the photocurable resin. 
 
     
     
       8. The manufacturing method according to  claim 7 , further comprising:
 in fixing the optical fibers, forming the fixing portion by accommodating the middle portion in a case and injecting the resin into the case; 
 in cutting the optical fibers, dividing the case into a first case divided body integrally fixed to the first bundle and a second case divided body integrally fixed to the second bundle by cutting the case together with the optical fibers; and 
 in optically connecting the divided optical fibers, positioning the divided optical fibers by positioning the first case divided body and the second case divided body. 
 
     
     
       9. The manufacturing method according to  claim 4 , further comprising:
 in cutting the optical fibers, dividing the case into a first case divided body integrally fixed to the first bundle and a second case divided body integrally fixed to the second bundle by cutting the case together with the optical fibers; and 
 in optically connecting the divided optical fibers, positioning the divided optical fibers by positioning the first case divided body and the second case divided body.